Radio frequency receivers are used in a large number of different types of applications, including various communication and sensing applications. Communication and sensing applications can include, but are not limited to, those associated with stationary and mobile stations and equipment, access points (APs), mobile devices, positioning systems (e.g., the Global Positioning System (GPS)), cellular telephones, radars, modems, light sensors, heat sensors, targeting sensors, networks, etc. Such applications can utilize receivers operating within one or more of a number of different radio frequency (RF) bands.
Receivers can operate within any one or more of the following frequency bands: Global System for Mobile Communications (GSM) bands, 850, 900, 1800, and/or 1900, Wideband Code Division Multiple Access (WCDMA) bands, High Speed Packet Access (HSPA) bands and/or Long Term Evolution (LTE) bands 1, 2, 3, 802.11 bands, GPS bands, etc. The frequency bands listed above are exemplary and not listed in a limiting fashion. Receivers can be employed in any workstation, telephone, desktop computer, laptop, notebook computer, server, handheld computer, mobile telephone, other portable telecommunications device, media playing device, a gaming system, mobile computing device, sensor, radar, or any other type and/or form of sensing, computing, telecommunication or media device.
Radio receivers often utilize a converter or demodulator to process radio frequency signals. The converter or demodulator converts the radio frequency signal to a baseband (BB) signal (e.g., an analog baseband signal). Communication and sensing devices have employed direct conversion receivers comprised of at least one passive mixer that utilizes triode transistors. CMOS devices associated with the analog baseband signal can exhibit strong 1/f noise (also known as flicker noise).